1. Field of the Invention
The present invention relates to packaging materials with electromagnetic coupling modules, and more particularly, to a packaging material with an electromagnetic coupling module having a radio IC chip used in an RFID (Radio Frequency Identification) system.
2. Description of the Related Art
Recently, RFID systems, in which a reader/writer that generates an induction field contactlessly communicates with an IC chip (also referred to as an IC tag and a radio IC chip) that is attached to an article or a container and stores predetermined information to exchange information, have been developed as article management systems. For example, Japanese Unexamined Patent Application Publication No. 2003-26177 discloses a packaging body having an antenna unit and an IC chip that are electrically conductive and provided on an outer surface of a cardboard box. Covering the IC chip with another surface to protect the IC chip is also described.
However, attaching the antenna unit and the IC chip onto the outer surface of the packaging body has a problem of being easily influenced by an external environment, and furthermore, increased thickness areas are provided because the attachment areas project outwardly, whereby accurate stacking such as when stacking and storing the packaging bodies is difficult. When another article contacts the projecting IC chip, the IC chip may be damaged by the shock. The antenna unit and the IC chip must be arranged to overlap each other in an electrically conductive manner. Since the displacement in the overlapping state causes trouble in transmission and reception of signals, high accuracy is required with this arrangement. Furthermore, the radiation characteristic during transmission and reception may not be sufficient since the antenna unit is relatively small.